It’s all quite silly but surprisingly effective, thanks to the taunt direction of James Wan (creator of the “Saw” series) and a cast of talented pros who keep our doubts at arm’s length.

“The Conjuring” is inspired by the ghostly experiences of husband-and-wife team of Ed and Lorraine Walker, who specialized in paranormal investigations. These real-life ghostbusters did on-site studies of hauntings publicized in the movies like “The Amityville Horror “ and “A Haunting in Connecticut.”

The Walkers are portrayed here by Patrick Wilson and Vera Farmiga, very fine actors who bring a matter of factness to the eerie proceedings that borders on the subversive. They’re just an old married couple who chat about demonic possession the way a farmer and his wife might discuss whether to plant the north forty with soybeans or sorghum.

Patrick Wilson, Vera Farmiga

We see the Walkers working on several cases – not all of which involve the supernatural…sometimes that creepy creaking is the result of a settling foundation – and then they are called to the rural Rhode Island home of Roger and Carolyn Perron (Ron Livingston, Lili Taylor) and their five daughters.

Shortly after moving into the old manse the Perrons began experiencing weird happenings…events that became so violent that they sought professional help.

Wan and his screenwriters – Chad and Carey Hayes – do a very nice job of slowly tightening the screws, creating an atmosphere of growing dread. (Also, they have compressed the Perron’s decade of ghostly persecution into a window of just a few weeks.)

The acting is perfectly adequate, but this isn’t an actor’s movie. It’s all about the plot, about the atmosphere, about the shock effects. In fact, even the major characters seem to have been shorn of all rough edges…these are generic people. The five Perron girls are virtually interchangeable.